A Study of the Effects of Low Power Plasma Treatment on Graphite and Highly Orientated Pyrolytic Graphite (HOPG) Surfaces

We have studied both the chemical and topographical changes induced on graphitic surfaces by low power plasmas using surface-sensitive X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), and atomic force microscopy (AFM). Evidence is presented for two totally different reaction mechanisms for air plasma and nitrogen plasma interactions with these surfaces. Both plasmas chemically alter the first few atomic layers of the surface; however, air plasma treatment results in the formation of an oxidised layer, whereas nitrogen plasma treatment generates a much more open structure of loosely adhered material.